2 For
Examiner’s
Use
1 A large plastic ball is dropped from the top of a tall building.
Fig. 1.1 shows the speed-time graph for the falling ball until it hits the ground.
20
15
speed
m / s 10
0
0 1 2 3 4 5 6
time / s
Fig. 1.1
(a) From the graph estimate,
(i) the time during which the ball is travelling with terminal velocity,
time = ................................................ [1]
(ii) the time during which the ball is accelerating,
time = ................................................ [1]
(iii) the distance fallen while the ball is travelling with terminal velocity,
distance = ................................................ [2]
(iv) the height of the building.
height = ................................................ [2]
© UCLES 2007 0625/03/O/N/07
3 For
Examiner’s
Use
(b) Explain, in terms of the forces acting on the ball, why
(i) the acceleration of the ball decreases,
..................................................................................................................................
..................................................................................................................................
..................................................................................................................................
............................................................................................................................ [3]
(ii) the ball reaches terminal velocity.
..................................................................................................................................
............................................................................................................................ [2]
[Total: 11]
© UCLES 2007 0625/03/O/N/07 [Turn over
